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871.
C om m ent Silver and zinc salts of sulfadiazine are widely used to prevent bacterial infection for both hum ans and anim als during burn treatm ents[1~4]. Because the slow release of the m etal ions highly relevant to the biologicalactivity ofthese polym… 相似文献
872.
以硝酸锌、樟脑酸(H2CAM)和1,2-二咪唑基二甲苯(obix)或4,4′-二咪唑基二甲联苯(bimb)为原料,在水热条件下得到2个结构不同的配位聚合物[Zn(obix)(CAM)]n(1)和[Zn(bimb)(CAM)]n(2)。对它们进行了元素分析、红外光谱和热重等分析,并利用X-射线洐射测定了它们的单晶结构。配合物1中2个锌离子通过2个obix配体桥连成一个24元大环,它再通过CAM配体连接成一维管状结构,而配合物2中锌离子通过两种配体桥连成二维层状结构。结果说明了辅助配体在配合物组装过程中起着非常重要的作用。此外还研究了它们的荧光性质。 相似文献
873.
Complex [Mn(tce) 0.5(H2O) 4](1) was obtained from Mn(OAc) 2 and tce,where tce is 1,1,2,2-tetracarboxyl-ethane. The structure of 1 is a single molecule,in which Mn(II) is a distorted octahedron coordinated to six oxygen atoms. Complex [Cd(tce) 0.5(H2O) 3](H2O) (2) fea-tures a pillared layer architecture. The Cd(II) atom is in an octahedral environment coordinated by six oxygen donors from water molecules and tce ligands. Cd(II) atoms are interlinked by the tce ligand to generate a 2-D wavelike layer. The layers are strutted by the intermolecular O-H···O hydrogen bonds to form a 3-D open framework. Luminescence property of complex 2 was investigated. Magnetic property of complex 1 was also studied. 1 belongs to triclinic,space group P1 with a = 6.2901(12) ,b = 8.0212(15) ,c = 8.0769(15) ,α = 108.522(3) ,β = 95.068(3) ,γ = 97.086(3) °,V = 379.92(12) 3,Mr = 456.08,Dc = 1.993 g/cm3,F(000) = 232,μ = 1.748 mm-1,Z = 1,the final R = 0.0297 and wR = 0.0731 for 1575 observed reflections with I > 2σ(I) . 2 is of monoclinic system,space group P21/c with a = 6.4367(14) ,b = 9.495(2) ,c = 13.907(3) ,β = 117.405(8) °,V = 754.6(3) 3,Mr = 285.51,Dc = 2.513 g/cm3,F(000) = 556,μ = 2.905 mm-1,Z = 4,the final R = 0.0375 and wR = 0.0737 for 1521 observed reflections with I > 2σ(I). 相似文献
874.
通过水热法合成了一个新的金属-有机配位聚合物[Zn(pzdc)(bix)0.5(H2O)]n(1)(H2pzdc=吡嗪-2,3-二甲酸,bix=1,4-双(咪唑基1-甲基)-苯)。并对其进行了元素分析、红外光谱、紫外光谱和X-射线单晶衍射测定。该配合物属于三斜晶系,P1空间群。晶体学数据:a=0.737 27(8),b=1.004 45(12),c=1.079 10(13)nm,α=113.771(2),β=102.005(2),γ=93.586(2)°,V=0.705 71(14)nm3,C13H11N4O5Zn,Mr=368.63,Dc=1.735 g.cm-3,μ(Mo Kα)=1.773 mm-1,F(000)=374,Z=2,最终R=0.027 6,wR=0.067 7用于2 460个可观测点。在晶体结构中,锌离子通过吡嗪-2,3-二甲酸和1,4-双(咪唑基1-甲基)-苯)配体桥联成二维层状结构。而且该配合物通过氢键和π-π堆积作用扩展成三维超分子网状结构。此外还研究了它的荧光性质。 相似文献
875.
利用3-吲哚乙酸(IAA)、邻菲啰啉(o-phen)和氯化锌在水-乙醇体系合成了一种金属配合物[Zn(IAA)2(o-phen)](1),并对其进行了X-射线单晶衍射分析、热重分析、元素分析、红外光谱、紫外光谱、荧光光谱表征。结构分析表明,该配合物中,锌离子处于四配位的四面体构型中,分别与2个IAA阴离子的羧基氧原子及1个邻菲啰啉的2个氮原子配位。通过超分子作用力:氢键和面对面式的π…π堆积作用力的自组装作用使这些分子形成二维的超分子层结构,继而这些层层间通过边对面式的π…π堆积作用力进一步的组装成三维的超分子结构。热重分析显示,该配合物具有较高的热稳定性。配合物的液态及固体荧光性质研究表明,此配合物具有一定荧光性质。 相似文献
876.
邻苯三酚在碱性溶液中的自氧化反应产生超氧阴离子自由基(O2-.),可迅速氧化天青Ⅰ褪色。中药提取物可以抑制O2-.氧化天青Ⅰ褪色,根据该原理建立了一种测定中药对O2-.清除率的新方法。测定体系最佳实验条件为pH 9.0,天青Ⅰ用量为5.0 mL,邻苯三酚用量为0.8 mL,反应时间9 min。测得六种中药的提取液清除O2-.的效果,结果表明,清除能力顺序为:车前子>枸杞>川芎>当归>茯苓>射干。 相似文献
877.
A new binuclear Cu(Ⅱ) complex with nitronyl nitroxide radicals [Cu(NIT3Py)2Cl2]2(NIT3Py = 2-(3'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in monoclinic,space group C2/c with a = 38.483(4),b = 7.2450(8),c = 27.559(3) ,β = 134.0180(10)°,V = 5525.6(10) 3,C48H64Cl4Cu2N12O8,Mr = 1206.00,Z = 4,Dc = 1.450 g/cm3,μ(MoKα) = 1.025 mm-1,F(000) = 2504,S = 1.066,the final R = 0.0471 and wR = 0.1121 for 3286 observed reflections(I > 2σ(I)).The title complex consists of centrosymmetric dinuclear units [Cu(NIT3Py)2Cl2]2,in which the copper ions are square-pyramidally coordinated by two pyridyl nitrogen atoms of two radical ligands and three chlorine anions,two of which bridge the copper ions.The magnetic measurements show ferromagnetic interactions between the copper ions and the radical ligands. 相似文献
878.
Reactions of pyridine-2,6-dicarboxylic acid(H2PDA) with cobalt(Ⅱ) acetate resul-ted in two cobalt(Ⅱ) complexes,[Co(HPDA)2].2H2O.0.5CH3OH(1) and [Co2(PDA)2(H2O)5].2H2O(2),which were characterized by single-crystal X-ray diffraction,IR and electronic absorption spectra.For both complexes,every cobalt atom lies in peudo-octahedral coordination geometry,and the whole structures present 3D frameworks linked by π-π stacking interactions and extensive hydrogen bonds.Magnetic studies showed λ =-83.38 cm-1 for(1) and g = 2.50 and J =-1.38 cm-1 for(2). 相似文献
879.
Three novel complexes [Cu(L1)2(H2O)2] (1), [Ni(L1)2(H2O)2]·(H2O)4(2,HL1=5-methyl-1-(4-methylphenyl)-1,2,3-triazole-4-carboxylic acid) and [Ni2 (HL2)2(CH3OH)6]·(CH3OH)2(3,H3L2=1,2,3-triazole-4,5-dicarboxylic acid) were synthesized and characterized by elemental analysis, IR and X-ray diffraction. Complexes 1 and 2 are mononuclear structures, and are assembled into a two-dimensional sheet by C(7) H(7)···O(3) weak interactions or hydrogen-bonding interaction. Complex 3 is a centrosymmetric dinuclear structure, and is assembled into a three-dimensional supramolecular structure by hydrogen-bonding interaction. 相似文献
880.
ZHAN Ming-Jian LIU Xiao-Hui ZHANG Qi-Sheng WANG Bing-Xi CHENG Yan-Xiang LU Can-Zhong 《结构化学》2012,31(8):1145-1151
Four novel Cu(Ⅰ) complexes,[Cu(o-PYO)(PPh3)2]BF4(1),[Cu(o-PYO)(DPEphos)]BF4(2),[Cu2 (o-PYO)(PPh3)3(CH3CN)](BF4)2(3) and [Cu2(o-PYO)(DPEphos)2 ](BF4)2(4) (o-PYO=2,5bis(pyridyl)-1,3,4-oxadiazole,PPh 3=triphenylphosphine,DPEphos=bis(2-(diphenylphosphanyl)phenyl)ether),have been synthesized and characterized by 1 H NMR,elemental analysis and single-crystal X-ray diffraction.The central cuprous ions in all complexes are surrounded by N and P atoms to form a distorted tetrahedral geometry,although one of the cuprous ions in complex 3 is coordinated by a PPh3 and an acetonitrile molecule due to the steric hindrance and weak coordination ability from monodentate PPh3 ligand.The UV-vis absorption spectra in CH2Cl2 show the characteristic metal-to-ligand charge transfer (MLCT) absorption bands in the region of 360-480nm.Four Cu(I) complexes exhibit yellow to orange-red phosphorescence with the emission maximum at 572,577,562 and 597nm,respectively in the solid state. 相似文献